This question has been a subject to legal arguments, especially in Israel but also outside of it. There have been court cases in Israel since 1962 which had to address the question. In addition, a United Kingdom court has had to consider whether the question was a racial issue or not, and so have many other countries.

According to the simplest definition used by Jews in order to identify themselves, a person is a Jew either by birth or by religious conversion. However, again, there are differences of opinion among the various about the matter. Therefore, the following need to be taken into account: